Made slightly different as I just used one piece of blue foam ( and a couple pieces of meat tray depron) folded to the middle like you would fold a paper airplane, this might result in a slightly steeper wing sweep @ 45deg.? I used a carbon arrow shaft for a spar just ahead of the motor, glued in with gorilla glue and weighted overnight. The next day I folded the top wing section over and glued in the same manner to top of spar.
I cut out the payload bay and will leave it open most likely as it doesn't seem to mind, this will carry FPV gear in the future. The ailerons are the cut out sections from the trailing edge flipped side-to-side and taped on.
Flew great on first toss with very little trim required.